The latest firmware updates for the EOS 5D Mark II is available from the Canon website.
To find the updates:
- Follow -> this link to the Drivers & Software area for the EOS 5D Mark II
- Select the type of operating system you use (Windows or Macintosh), and the version you use.
- Click "Firmware" and then the link "EOS 5D Mark II, Firmware Version 2.1.2 [xxxxxxxxxx]"
- Download the zipped firmware file to your hard drive and extract the .FIR firmware update file.
- Copy the extracted .FIR file to the root directory of a CF memory card by inserting the card into a card reader and dragging/dropping the file to the card.
- Install the CF card into your camera and call up Firmware Ver. x.x.x. in your camera's 3rd set-up menu (with the yellow wrench).
- Select OK when asked if you want to upgrade to the new version
Note that full PDF instructions for the upgrade procedure will accompany the firmware upgrade when you download the zipped file from the site. Be sure to read and thoroughly understand the steps before attempting to install the firmware into your camera